The present invention relates to an amorphous silicon image sensor, and, more particularly, to a contact type amorphous silicon image sensor. A contact type amorphous silicon image sensor is constituted by a photosensor array which comprises: a lower electrode vapored deposited on the upper surface of-a transparent substrate; an a-Si film (amorphous silicon film) with a multilayered structure which covers one end portion of the lower electrode; a transparent conductive film covering the uppermost surface of the amorphous silicon film; and an upper electrode vapor deposited on the transparent substrate in such a manner that this upper electrode covers one end portion of the transparent electrode. This photosensor array is covered with a transparent insulating film which serves as a protection layer.